Various variable displacement internal combustion engine designs are known in the art. Such designs include (i) deactivating one or more cylinders of an engine, such as by cutting off fuel supply to selected cylinders, and (ii) split-engine designs, where one group of cylinders (a cylinder bank) operates independently from another cylinder bank.
U.S. Pat. No. 7,024,858 to Gray, U.S. Pat. No. 4,566,279 to Kronogard, and U.S. Pat. No. 6,306,056 to Moore, each disclose split-engine variable displacement engines with an individual crankshaft provided for each independent cylinder bank in the engine, with the cylinder banks fed from a common fuel source and residing in a common engine block.
While the above-mentioned engine designs provide the potential for improved engine efficiency, it is nevertheless desirable to develop further engine designs with even greater efficiency potential.